Hipparchus 5.1°S, 5.2°E

Hipparchus is a giant, heavily ruined crater, with a diameter of 138 km and a depth of 3 km, which arose in the Pre-Nectarian period. The southeast crater wall is broken split by two deep, broad gaps. The northwestern wall of the crater is likewise largely destroyed, and exhibits wide gorges that are open towards Rima Réaumur (about 30 km long) and to Sinus Medii. Rima Réaumur encounters Rima Oppolzer at almost a right angle. Both are linear fracture zones, probably associated with the lava surface of Sinus Medii.

The floor of Hipparchus exhibits mountain peaks, small hills, crater pits, ghost craters and the 30-km, well-preserved, young crater Horrocks. The southwestern crater wall of Hipparchus is almost completely destroyed, and is covered with a group of both large and small craters.

The crater walls of Hipparchus generally consist of a series of holes, furrows, rilles, hills and ridges. The pattern that these features exhibit is radial to the centre of the Imbrium Basin. They are part of the Imbrium Sculpture and may be followed over a distance of more than 1000 km.

Albategnius 11.7°S, 4.3°E

Albategnius is a prominent, very conspicuous complex crater with a diameter of 114 km, an imposing central peak and a flat, smooth crater floor. The inner walls have been heavily eroded by landslides and intervening valleys, and is saturated with craterlets. The western crater wall is overlapped by the 44-km wide crater Klein. Under grazing illumination at sunrise (waxing Moon), numerous, very shallow, circular depressions are visible. Two of these lie directly to the east of the central peak, and two more to the south. The highest summit on the central peak has a pit that is about 1 km in diameter.